Towards a more realistic configuration to simulate the settling of finite-size particles in the dilute regime

Simulating the settling of particles in the dilute regime is a very complex problem which, thanks to the relatively recent maturity reached by immersed boundary methods, we can analyze by means of particle-resolved direct numerical simulations. The cost of these simulations is still very high and one of the assumptions typically made by the authors to reduce the complexity of the problem is the use of a triply periodic configuration. This configuration has shown to be very successful to understand the onset of clustering, but the analysis of cluster dynamics is not possible because of the strong correlation of the solution in the vertical direction. In this talk we present preliminary results of the settling of particles in a configuration where the periodicity in the vertical direction is removed. The advantages and challenges of using this configuration will be also briefly discussed. In order to exploit our previous knowledge on the settling of particles we set the Galileo number to 121 and 178 and the particle-to-fluid density ratio to 1.5 based on the work of Uhlmann and Doychev (2014). We observe a similar clustering behavior as in the triply periodic counterpart, but at a higher particle concentration.